The Sequential Combination of FOLFOX and Toripalimab for Perioperative Immuno-Oncology Therapy of HER2-negative Adenocarcinoma of the Esophagogastric Junction (Siewert I/II):

The addition of immunotherapy to chemotherapy improves outcomes in patients with HER2-negative gastroesophageal adenocarcinoma (GEA), and investigators aim to explore its role in the perioperative setting. Moreover, optimizing the timing schedule of these two therapies is critical when balancing efficacy and safety. This Chinese, multicenter, open-label phase 1b/2 trial will evaluate the efficacy and toxicity of perioperative folinic acid, fluoro-uracil, oxali-platin (FOLFOX), and toripalimab (JS001, a novel PD-1 inhibitor) in combination at various schedules in the neoadjuvant setting in patients with HER2-negative resectable GEA: three cycles each in Arm A: FOLFOX (D1, q2w) followed by toripalimab (D3, 3 mg/kg, q2w); Arm B: concurrent FOLFOX (D1, q2w) combined with toripalimab (D1, 3 mg/kg, q2w); Arm C: toripalimab (D1, 3 mg/kg, q2w) followed by FOLFOX (D3, q2w); Arm D: FOLFOX (D1, q2w) alone. The primary end-point is the dose-limiting toxicity in Phase 1b and the pathological complete response rate in Phase 2; secondary end-points include major pathologic response, disease-free survival, and event-free survival.A fixed sample size of 126 patients is used in this study, with a safety run-in period (n = 6) and cohort expansion period (n = 24), a dropout rate of 5% within 12 months of follow-up. Each arm receives three cycles of FOLFOX (D1, q2w) followed by 15 cycles of toripalimab (D1, 240 mg, q3w) in the neoadjuvant setting. Pre-treatment biopsies, post-resection specimens, serial liquid biopsy, and gut microbiota samples on treatment will be collected to explore the biomarkers' predictive value on diverse schedule efficacy and safety.

This Chinese, multicenter, open-label phase 1b/2 trial will evaluate the efficacy and toxicity of perioperative folinic acid, fluoro-uracil, oxali-platin (FOLFOX), and toripalimab (JS001, a novel PD-1 inhibitor) in combination at various schedules in the neoadjuvant setting in patients with HER2-negative resectable GEA: three cycles each in Arm A: FOLFOX (D1, q2w) followed by toripalimab (D3, 3 mg/kg, q2w); Arm B: concurrent FOLFOX (D1, q2w) combined with toripalimab (D1, 3 mg/kg, q2w); Arm C: toripalimab (D1, 3 mg/kg, q2w) followed by FOLFOX (D3, q2w); Arm D: FOLFOX (D1, q2w) alone. The primary end-point is the dose-limiting toxicity in Phase 1b and the pathological complete response rate in Phase 2; secondary end-points include major pathologic response, disease-free survival, and event-free survival. A fixed sample size of 126 patients is used in this study, with a safety run-in period (n = 6) and cohort expansion period (n = 24), a dropout rate of 5% within 12 months of follow-up. Each arm receives three cycles of FOLFOX (D1, q2w) followed by 15 cycles of toripalimab (D1, 240 mg, q3w) in the neoadjuvant setting. Pre-treatment biopsies, post-resection specimens, serial liquid biopsy, and gut microbiota samples on treatment will be collected to explore the biomarkers' predictive value on diverse schedule efficacy and safety.